1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
|
/*-
* Copyright (c) 2012 Alexander Rybalko <ray@freebsd.org>
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/watchdog.h>
#include <sys/bus.h>
#include <sys/kernel.h>
#include <sys/module.h>
#include <sys/rman.h>
#include <dev/fdt/fdt_common.h>
#include <dev/ofw/openfirm.h>
#include <dev/ofw/ofw_bus.h>
#include <dev/ofw/ofw_bus_subr.h>
#include <machine/bus.h>
#include <machine/machdep.h>
#include <arm/broadcom/bcm2835/bcm2835_wdog.h>
#define BCM2835_PASWORD 0x5a
#define BCM2835_WDOG_RESET 0
#define BCM2835_PASSWORD_MASK 0xff000000
#define BCM2835_PASSWORD_SHIFT 24
#define BCM2835_WDOG_TIME_MASK 0x000fffff
#define BCM2835_WDOG_TIME_SHIFT 0
#define READ(_sc, _r) bus_space_read_4((_sc)->bst, (_sc)->bsh, (_r) + (_sc)->regs_offset)
#define WRITE(_sc, _r, _v) bus_space_write_4((_sc)->bst, (_sc)->bsh, (_r) + (_sc)->regs_offset, (_v))
#define BCM2835_RSTC_WRCFG_CLR 0xffffffcf
#define BCM2835_RSTC_WRCFG_SET 0x00000030
#define BCM2835_RSTC_WRCFG_FULL_RESET 0x00000020
#define BCM2835_RSTC_RESET 0x00000102
#define BCM2835_RSTC_REG 0x00
#define BCM2835_RSTS_REG 0x04
#define BCM2835_WDOG_REG 0x08
static struct bcmwd_softc *bcmwd_lsc = NULL;
struct bcmwd_softc {
device_t dev;
struct resource * res;
bus_space_tag_t bst;
bus_space_handle_t bsh;
int wdog_armed;
int wdog_period;
char wdog_passwd;
struct mtx mtx;
int regs_offset;
};
#define BSD_DTB 1
#define UPSTREAM_DTB 2
#define UPSTREAM_DTB_REGS_OFFSET 0x1c
static struct ofw_compat_data compat_data[] = {
{"broadcom,bcm2835-wdt", BSD_DTB},
{"brcm,bcm2835-pm-wdt", UPSTREAM_DTB},
{NULL, 0}
};
static void bcmwd_watchdog_fn(void *private, u_int cmd, int *error);
static int
bcmwd_probe(device_t dev)
{
if (!ofw_bus_status_okay(dev))
return (ENXIO);
if (ofw_bus_search_compatible(dev, compat_data)->ocd_data == 0)
return (ENXIO);
device_set_desc(dev, "BCM2708/2835 Watchdog");
return (BUS_PROBE_DEFAULT);
}
static int
bcmwd_attach(device_t dev)
{
struct bcmwd_softc *sc;
int rid;
if (bcmwd_lsc != NULL)
return (ENXIO);
sc = device_get_softc(dev);
sc->wdog_period = 7;
sc->wdog_passwd = BCM2835_PASWORD;
sc->wdog_armed = 0;
sc->dev = dev;
rid = 0;
sc->res = bus_alloc_resource_any(dev, SYS_RES_MEMORY, &rid, RF_ACTIVE);
if (sc->res == NULL) {
device_printf(dev, "could not allocate memory resource\n");
return (ENXIO);
}
sc->bst = rman_get_bustag(sc->res);
sc->bsh = rman_get_bushandle(sc->res);
/* compensate base address difference */
if (ofw_bus_search_compatible(dev, compat_data)->ocd_data
== UPSTREAM_DTB)
sc->regs_offset = UPSTREAM_DTB_REGS_OFFSET;
bcmwd_lsc = sc;
mtx_init(&sc->mtx, "BCM2835 Watchdog", "bcmwd", MTX_DEF);
EVENTHANDLER_REGISTER(watchdog_list, bcmwd_watchdog_fn, sc, 0);
return (0);
}
static void
bcmwd_watchdog_fn(void *private, u_int cmd, int *error)
{
struct bcmwd_softc *sc;
uint64_t sec;
uint32_t ticks, reg;
sc = private;
mtx_lock(&sc->mtx);
cmd &= WD_INTERVAL;
if (cmd > 0) {
sec = ((uint64_t)1 << (cmd & WD_INTERVAL)) / 1000000000;
if (sec == 0 || sec > 15) {
/*
* Can't arm
* disable watchdog as watchdog(9) requires
*/
device_printf(sc->dev,
"Can't arm, timeout must be between 1-15 seconds\n");
WRITE(sc, BCM2835_RSTC_REG,
(BCM2835_PASWORD << BCM2835_PASSWORD_SHIFT) |
BCM2835_RSTC_RESET);
mtx_unlock(&sc->mtx);
return;
}
ticks = (sec << 16) & BCM2835_WDOG_TIME_MASK;
reg = (BCM2835_PASWORD << BCM2835_PASSWORD_SHIFT) | ticks;
WRITE(sc, BCM2835_WDOG_REG, reg);
reg = READ(sc, BCM2835_RSTC_REG);
reg &= BCM2835_RSTC_WRCFG_CLR;
reg |= BCM2835_RSTC_WRCFG_FULL_RESET;
reg |= (BCM2835_PASWORD << BCM2835_PASSWORD_SHIFT);
WRITE(sc, BCM2835_RSTC_REG, reg);
*error = 0;
}
else
WRITE(sc, BCM2835_RSTC_REG,
(BCM2835_PASWORD << BCM2835_PASSWORD_SHIFT) |
BCM2835_RSTC_RESET);
mtx_unlock(&sc->mtx);
}
void
bcmwd_watchdog_reset(void)
{
if (bcmwd_lsc == NULL)
return;
WRITE(bcmwd_lsc, BCM2835_WDOG_REG,
(BCM2835_PASWORD << BCM2835_PASSWORD_SHIFT) | 10);
WRITE(bcmwd_lsc, BCM2835_RSTC_REG,
(READ(bcmwd_lsc, BCM2835_RSTC_REG) & BCM2835_RSTC_WRCFG_CLR) |
(BCM2835_PASWORD << BCM2835_PASSWORD_SHIFT) |
BCM2835_RSTC_WRCFG_FULL_RESET);
}
static device_method_t bcmwd_methods[] = {
DEVMETHOD(device_probe, bcmwd_probe),
DEVMETHOD(device_attach, bcmwd_attach),
DEVMETHOD_END
};
static driver_t bcmwd_driver = {
"bcmwd",
bcmwd_methods,
sizeof(struct bcmwd_softc),
};
static devclass_t bcmwd_devclass;
DRIVER_MODULE(bcmwd, simplebus, bcmwd_driver, bcmwd_devclass, 0, 0);
|